Open AccessExtensive nuclear gyration and pervasive non-genic transcription during primordial germ cell development in zebrafish
Author(s) -
Stefan Redl,
António Miguel de Jesus Domingues,
Edoardo Caspani,
Stefanie Möckel,
Willi Salvenmoser,
María Méndez-Lago,
René F. Ketting
Publication year - 2020
Publication title -
development
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.15
H-Index - 36
eISSN - 1477-9129
pISSN - 0950-1991
DOI - 10.1242/dev.193060
Subject(s) - biology , zebrafish , piwi interacting rna , microbiology and biotechnology , chromatin , genetics , polarity in embryogenesis , gene , transcription (linguistics) , germ cell , transcription factor , transposable element , embryonic stem cell , genome , gastrulation , linguistics , philosophy
Primordial germ cells (PGCs) are the precursors of germ cells, which migrate to the genital ridge during early development. Relatively little is known about PGCs after their migration. We studied this post-migratory stage using microscopy and sequencing techniques, and found that many PGC-specific genes, including genes known to induce PGC fate in the mouse, are only activated several days after migration. At this same time point, PGC nuclei become extremely gyrated, displaying general broad opening of chromatin and high levels of intergenic transcription. This is accompanied by changes in nuage morphology, expression of large loci (PGC-expressed non-coding RNA loci, PERLs) that are enriched for retro-transposons and piRNAs, and a rise in piRNA biogenesis signatures. Interestingly, no nuclear Piwi protein could be detected at any time point, indicating that the zebrafish piRNA pathway is fully cytoplasmic. Our data show that the post-migratory stage of zebrafish PGCs holds many cues to both germ cell fate establishment and piRNA pathway activation.